U.S. Pat. No. 5,662,704 issued Sep. 2, 1997 and entitled "Physiological Mitral Valve Bioprosthesis" describes the selection, preparation and positioning of a xenograft such as a porcine mitral valve for valve replacement surgery in the human heart.
As will be readily appreciated from that discussion, the orientation of the annulus and papillary heads of a xenograft mitral valve is three-dimensional in nature. This also holds true for a stentless physiological mitral valve (PMV). Both the PMV's annulus and papillary heads are free to distort when the valve is held in one's hand or when the valve is implanted in the mitral position of a recipient. If the valve is implanted in a distorted geometry, both hemodynamic performance and long term durability could suffer. It is therefore desirable to hold the prosthesis temporarily in its optimum geometric configuration so that the valve may be implanted properly. Once the valve's implantation orientation is set relative to the patient's left ventricular geometry, the temporary holder is removed. The implantation position of the valve in the left ventricle then provides the necessary rigidity and structure for valve function.
Temporary holding systems for holding implants have previously been used in annuloplasty. They have not, however, been used in stentless mitral xenografts because that type of surgery poses more complex problems than does annuloplasty. Consequently, a need exists for a temporary holder system suitable for the placing of non-stented chordally supported mitral xenograft valves, or pericardial and synthetic derivatives of the natural mitral valve in which temporary geometric positioning is necessary to facilitate implantation.